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Biology Edexcel Sophie > Topic 6 Forensics And immunity > Flashcards

Topic 6 Forensics And immunity Flashcards

1
Q

What role do microorganisms play in the decomposition of organic matter?

A

Microorganisms, such as bacteria and fungi, decompose dead organic matter into small molecules that they can respire.

This process is essential for recycling carbon back into the atmosphere.

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2
Q

What gases are released when microorganisms respire small molecules during decomposition?

A

Methane (CH₄) and carbon dioxide (CO₂)

These gases are part of the carbon cycle.

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3
Q

What is the significance of determining the time of death (TOD) in forensics?

A

Establishing the TOD can provide information about the circumstances of death and who was present.

It can help police and forensic scientists in their investigations.

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4
Q

What is algor mortis?

A

The process by which a dead body’s temperature falls until it equals the temperature of its surroundings.

This occurs after death as metabolic reactions slow down.

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5
Q

At what rate does a human body typically cool after death?

A

Around 1.5 °C to 2.0 °C per hour.

This cooling rate can be affected by environmental factors.

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6
Q

What is rigor mortis?

A

The stiffening of muscles that occurs approximately 4-6 hours after death.

It begins when muscle cells are deprived of oxygen.

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7
Q

What causes rigor mortis?

A

The lack of ATP due to anaerobic respiration leads to the fixation of myosin and actin bonds in muscle cells.

This results in muscle stiffness.

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8
Q

How does temperature affect rigor mortis?

A

Rigor mortis occurs more quickly at higher temperatures because chemical reactions in the body are faster.

This can influence the timing of death estimations.

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9
Q

What is forensic entomology?

A

The study of insects that colonize a dead body to estimate the time of death.

It often involves identifying the types of insects present.

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10
Q

How can the time of death be estimated using insect life cycles?

A

By identifying the type of insect and the stage of its life cycle.

For example, blowfly larvae hatch from eggs about 24 hours after being laid.

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11
Q

What factors can affect the life cycle of insects on a decomposing body?

A

Drugs, humidity, oxygen, and temperature.

Higher temperatures can speed up metabolic rates and shorten life cycles.

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12
Q

What is the extent of decomposition in the first few days after death?

A

Cells and tissues are being broken down by bacteria and enzymes.

This process begins immediately after death.

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13
Q

What happens to the body after a few weeks of decomposition?

A

Tissues begin to liquefy and seep out into the area around the body.

This is part of the natural decomposition process.

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14
Q

What is the final stage of decomposition?

A

Only a skeleton remains after a few months to a few years.

Eventually, the skeleton disintegrates over decades to centuries.

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15
Q

What is succession in the context of a dead body?

A

The changing types of organisms found on a dead body over time.

This process helps forensic scientists estimate the time of death.

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16
Q

What conditions favor the initial colonization of a dead body?

A

Immediately after death, conditions are most favorable for bacteria.

This is followed by flies and their larvae.

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17
Q

Fill in the blank: The body begins to bloat due to gases produced during decomposition, such as ______.

A

[methane]

This bloating is a sign of microbial activity.

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18
Q

True or False: The stage of succession on a dead body is affected by its location.

A

True

For example, a body sealed away will not be colonized by insects.

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19
Q

What is a DNA profile?

A

A fingerprint of an organism’s DNA

Everyone’s DNA is unique except for identical twins.

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20
Q

What are the four bases that make up nucleotides in DNA?

A
  • A
  • T
  • C
  • G

These bases pair as A with T and C with G.

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21
Q

What is the purpose of DNA profiling?

A

To identify people and determine genetic relationships

This includes relationships between humans, animals, and plants.

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22
Q

What is the first step in creating a DNA profile?

A

A DNA sample is obtained from the organism

This can be collected from bodily fluids or tissues.

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23
Q

What process is used to amplify DNA for profiling?

A

Polymerase Chain Reaction (PCR)

PCR involves multiple stages to create many copies of DNA.

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24
Q

What components are included in a PCR reaction mixture?

A
  • DNA sample
  • Free nucleotides
  • Primers
  • DNA polymerase

Primers are short DNA sequences that initiate replication.

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25
Q

At what temperature does the DNA mixture need to be heated to break hydrogen bonds?

A

95 °C

This step denatures the DNA strands.

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26
Q

What is the purpose of cooling the mixture to between 50 and 65 °C during PCR?

A

To allow primers to bind (anneal) to the strands

This is essential for the subsequent DNA synthesis.

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27
Q

What temperature is used for DNA polymerase to synthesize new strands?

A

72 °C

This temperature is optimal for the enzyme’s activity.

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28
Q

How does the amount of DNA change with each PCR cycle?

A

It doubles each cycle

E.g., 1st cycle = 2 fragments, 2nd cycle = 4 fragments, etc.

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29
Q

What is the purpose of adding a fluorescent tag to DNA?

A

To visualize the DNA fragments under UV light

This helps in identifying and comparing DNA profiles.

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30
Q

How does gel electrophoresis separate DNA fragments?

A

By length

DNA moves towards the anode due to its negative charge.

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31
Q

What happens to shorter DNA fragments during gel electrophoresis?

A

They move faster and travel further

This results in separation according to length.

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32
Q

What do DNA profiles look like when viewed under UV light?

A

They appear as bands

The pattern of bands can be compared between profiles.

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33
Q

What is one application of DNA profiling in forensic science?

A

To link suspects to crime scenes

DNA from crime scene samples is compared to suspects’ DNA.

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34
Q

What is the first step a forensic scientist takes when collecting DNA from a crime scene?

A

Isolate DNA from collected samples

This includes samples from blood, semen, skin cells, etc.

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35
Q

What is the final step in comparing DNA profiles in forensic science?

A

Compare the PCR products on an electrophoresis gel

Matching profiles indicate a link to the crime scene.

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36
Q

What do we inherit from our parents in terms of DNA?

A

Roughly half comes from each parent.

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37
Q

What does it indicate if more bands on DNA profiles match?

A

The more closely-related (genetically similar) those two people are.

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38
Q

How can DNA profiling determine the biological father of a child?

A

By comparing DNA profiles; lots of matching bands suggest the individual is the child’s father.

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39
Q

What is one application of DNA profiling in animals and plants?

A

To prevent inbreeding, which causes health, productivity, and reproductive problems.

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40
Q

What is inbreeding and why is it problematic?

A

Inbreeding decreases the gene pool, leading to an increased risk of genetic disorders.

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41
Q

What is the relationship between DNA profile similarity and relatedness?

A

The more closely-related two individuals are, the more similar their DNA profiles will be.

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42
Q

What is the first step in carrying out gel electrophoresis?

A

Add a gel tray to a gel box (or tank).

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43
Q

What type of gel is commonly used for electrophoresis?

A

Agarose gel.

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44
Q

How are wells created in the gel for electrophoresis?

A

A row of wells is created at one end of the gel.

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45
Q

What is the purpose of the buffer solution in gel electrophoresis?

A

To cover the surface of the gel and facilitate the movement of DNA fragments.

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46
Q

What is the role of loading dye in DNA sample preparation?

A

It helps the samples to sink to the bottom of the wells and makes them easier to see.

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47
Q

How should DNA samples be added to the gel wells?

A

Using a micropipette, ensuring the tip is just above the opening of the well.

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48
Q

What happens when the power supply is turned on during electrophoresis?

A

An electrical current is passed through the gel, causing DNA fragments to separate according to length.

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49
Q

How long should the gel run during electrophoresis?

A

For about 30 minutes or until the dye is about 2 cm from the end of the gel.

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50
Q

What is the purpose of staining the DNA fragments after electrophoresis?

A

To make the bands of different DNA fragments visible.

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51
Q

How is the length of a DNA fragment measured?

A

In bases, e.g., ATCC = 4 bases or base pairs.

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52
Q

What does PCR stand for?

A

Polymerase Chain Reaction.

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53
Q

True or False: Identical twins have the same DNA profile.

A

True.

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54
Q

Briefly describe the procedure to separate DNA fragments by electrophoresis.

A

Prepare agarose gel, load DNA samples into wells, apply electric current, and visualize the results.

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55
Q

What is the significance of DNA profiling in forensic science?

A

It can provide conclusive proof of identity in criminal investigations.

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56
Q

Fill in the blank: The length of 1000 bases is referred to as _____ .

A

one kilobase (1 kb).

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57
Q

What type of cells are bacteria?

A

Bacteria are single-celled prokaryotic organisms

Prokaryotic means they have no nucleus.

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58
Q

What is the size of most bacteria?

A

Most bacteria are only a few micrometers (um) long, e.g. the TB bacterium is about 1 um.

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59
Q

What are the main components of bacterial cells?

A

Bacterial cells have:
* Plasma membrane
* Cytoplasm
* Ribosomes
* Cell wall
* Flagella
* Pili
* Capsule
* DNA (bacterial chromosome and plasmids)

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60
Q

What is the function of the flagellum in bacteria?

A

The flagellum is a long, hair-like structure that rotates to make the bacterium move.

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61
Q

What is the primary function of ribosomes in bacteria?

A

Ribosomes produce proteins from mRNA.

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62
Q

What is murein?

A

Murein is a component of the bacterial cell wall.

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63
Q

What are pili in bacteria used for?

A

Pili help bacteria stick to other cells and can be used in gene transfer.

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64
Q

What is the purpose of a bacterial capsule?

A

The capsule helps to protect the bacterium from attack by cells of the immune system.

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65
Q

How is bacterial DNA structured?

A

The DNA of a bacterium floats free in the cytoplasm and is typically in one long, circular, coiled-up strand called a bacterial chromosome.

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66
Q

What are plasmids?

A

Plasmids are small loops of DNA that aren’t part of the bacterial chromosome.

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67
Q

How do viruses differ from bacteria?

A

Viruses are not cells; they are nucleic acids surrounded by protein and are smaller than bacteria.

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68
Q

What components do viruses lack that bacteria have?

A

Viruses lack plasma membranes, cytoplasm, and ribosomes.

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69
Q

What is the function of the capsid in viruses?

A

The capsid is the protein coat around the core of a virus.

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70
Q

What is an envelope in the context of viruses?

A

An envelope is an extra outer layer that some viruses have, stolen from the cell membrane of a previous host cell.

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71
Q

What are attachment proteins in viruses used for?

A

Attachment proteins allow the virus to cling on to a suitable host cell.

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72
Q

Define a pathogen.

A

A pathogen is any organism that causes disease.

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73
Q

What are infectious diseases?

A

Diseases caused by pathogens.

74
Q

What type of microorganisms can be pathogenic?

A

Pathogenic microorganisms include some bacteria, some fungi, and all viruses.

75
Q

What is HIV’s primary method of replication?

A

HIV replicates inside the T helper cells of its host.

76
Q

What is reverse transcriptase?

A

An enzyme carried by HIV that is used to make complementary DNA from viral RNA.

77
Q

What happens during the latency period of HIV infection?

A

HIV replication drops to a lower level, and the infected person doesn’t experience symptoms.

78
Q

What condition does HIV eventually lead to?

A

HIV infection eventually leads to acquired immune deficiency syndrome (AIDS).

79
Q

What defines AIDS?

A

AIDS is a condition where the immune system deteriorates and eventually fails.

80
Q

What are opportunistic infections?

A

Infections that develop in people with a weakened immune system, typically seen in AIDS patients.

81
Q

List the initial symptoms of AIDS.

A

Initial symptoms of AIDS include:
* Minor infections of mucous membranes
* Recurring respiratory infections

82
Q

What serious infections can develop in late-stage AIDS?

A

Serious infections include:
* Toxoplasmosis of the brain
* Candidiasis of the respiratory system

83
Q

True or False: The length of time between HIV infection and the development of AIDS is the same for everyone.

A

False

84
Q

What factors affect the progression of HIV to AIDS?

A

Factors include:
* Existing infections
* Strain of HIV
* Age
* Access to health care

85
Q

What bacterium causes tuberculosis (TB)?

A

Mycobacterium tuberculosis

Mycobacterium tuberculosis is a slow-growing bacterium that primarily affects the lungs.

86
Q

How is tuberculosis (TB) contracted?

A

Infection occurs when tiny droplets containing the bacteria are inhaled into the lungs

These droplets can be released into the air when an infected person coughs or sneezes.

87
Q

What type of white blood cell engulfs Mycobacterium tuberculosis?

A

Phagocyte

Phagocytes are a type of immune cell responsible for engulfing and digesting pathogens.

88
Q

What happens to Mycobacterium tuberculosis inside phagocytes?

A

The bacteria survive and replicate

Mycobacterium tuberculosis can evade digestion and replicate within phagocytes.

89
Q

What structures in the lungs seal off infected phagocytes?

A

Tubercles

Tubercles are small, rounded structures formed by the immune response to contain the infection.

90
Q

What is a likely consequence of dormant Mycobacterium tuberculosis being reactivated?

A

It can cause tuberculosis (TB)

Reactivation is more likely in individuals with weakened immune systems.

91
Q

What are the initial symptoms of tuberculosis?

A

Fever, general weakness, and severe coughing

These symptoms are caused by inflammation of the lungs.

92
Q

What can untreated tuberculosis lead to?

A

Respiratory failure and organ failure

Left untreated, TB can cause severe complications that may lead to death.

93
Q

Through which routes can pathogens enter the body?

A

Through cuts in the skin, digestive system, respiratory system, and other mucosal surfaces

Each route poses a risk for different types of infections.

94
Q

What role does stomach acid play in preventing infection?

A

It kills most pathogens

Stomach acid is a significant barrier to pathogens ingested with food or drink.

95
Q

What is the function of skin flora?

A

They compete with pathogens for nutrients and space

Skin flora helps limit the number of pathogens that can colonize the skin.

96
Q

What enzyme is found in secretions from mucosal surfaces that helps kill bacteria?

A

Lysozyme

Lysozyme damages bacterial cell walls, leading to their destruction.

97
Q

What triggers the non-specific immune response?

A

Recognition of foreign antigens on the surface of a pathogen

This response is immediate and not specific to any particular pathogen.

98
Q

What are the signs of inflammation at the site of infection?

A

Redness, warmth, swelling, and pain

Inflammation is a key part of the immune response to infection.

99
Q

What process increases blood flow to the site of infection?

A

Vasodilation

Vasodilation is triggered by molecules released during the immune response.

100
Q

Fill in the blank: The immune system cells can then start to ______ the pathogen.

A

destroy

This is the ultimate goal of the immune response at the site of infection.

101
Q

What are interferons?

A

Proteins produced by infected cells to prevent virus spread.

Interferons play a crucial role in the immune response against viral infections.

102
Q

How do interferons prevent viral replication?

A

By inhibiting the production of viral proteins.

This action limits the ability of viruses to reproduce within host cells.

103
Q

What role do interferons play in the immune response?

A

They activate cells involved in the specific immune response and other mechanisms of the non-specific immune response.

This includes promoting inflammation to recruit immune cells.

104
Q

What is phagocytosis?

A

The process where a phagocyte engulfs and digests pathogens.

Phagocytes are essential for the non-specific immune response.

105
Q

What happens when a phagocyte encounters a pathogen?

A

It recognizes the antigens, engulfs the pathogen, and forms a phagocytic vacuole.

This vacuole contains the pathogen for digestion.

106
Q

What is the function of lysosomes in phagocytosis?

A

They fuse with phagocytic vacuoles and contain enzymes that break down pathogens.

Lysozymes are a key component in the destruction of engulfed pathogens.

107
Q

What are antigen-presenting cells?

A

Cells that present pathogen antigens on their surface to activate other immune cells.

Phagocytes, such as macrophages, serve this role.

108
Q

State four ways in which pathogens can enter the body.

A
  1. Respiratory tract
  2. Digestive tract
  3. Skin
  4. Urogenital tract
109
Q

State two barriers that prevent infection.

A
  1. Skin
  2. Mucous membranes
110
Q

What are antigens?

A

Substances that can trigger an immune response.

Antigens are typically found on the surface of pathogens.

111
Q

Describe two ways in which interferons prevent viruses from spreading to uninfected cells.

A
  1. Inhibit viral protein production
  2. Activate immune cells to kill infected cells
112
Q

How is inflammation triggered at the site of infection?

A

By the release of signaling molecules that increase blood flow and attract immune cells.

113
Q

How does inflammation aid the immune response?

A

It recruits immune cells to the site of infection and increases the permeability of blood vessels.

114
Q

What is the role of T cells in the immune response?

A

They recognize antigens and activate other immune cells.

T cells include helper, killer, and memory cells.

115
Q

What happens when a T cell binds to a complementary antigen?

A

It gets activated and divides to produce clones.

This process amplifies the immune response.

116
Q

What are the different types of T cells and their functions?

A
  • T helper cells - activate B cells and other immune cells
  • T killer cells - kill pathogen-infected cells
  • T memory cells - provide long-term immunity
117
Q

What are B cells covered with?

A

Proteins called antibodies.

118
Q

What do antibodies do?

A

They bind to antigens to form antigen-antibody complexes.

This interaction marks pathogens for destruction or neutralization.

119
Q

What occurs when a B cell’s antibody meets a complementary antigen?

A

The B cell is activated and divides into plasma cells and memory cells.

120
Q

What are plasma cells?

A

Clones of B cells that secrete antibodies specific to an antigen

Plasma cells are identical to B cells.

121
Q

What do antibodies consist of?

A

Four polypeptide chains: two heavy chains and two light chains

Each chain has a variable region and a constant region.

122
Q

What is the role of the variable region in antibodies?

A

Forms the antigen binding sites and is complementary to a particular antigen

The variable regions differ between antibodies.

123
Q

What is the function of the hinge region in antibodies?

A

Allows flexibility when the antibody binds to the antigen

124
Q

What do the constant regions of antibodies do?

A

Allow binding to receptors on immune system cells, e.g., phagocytes

The constant region is the same in all antibodies.

125
Q

What holds the polypeptide chains of antibodies together?

A

Disulfide bridges

126
Q

How do antibodies help to clear infections?

A

By agglutination, neutralizing toxins, and preventing pathogen binding

Each antibody can bind to two pathogens, clumping them together for phagocytosis.

127
Q

What is agglutination?

A

The clumping together of pathogens by antibodies

128
Q

What is the effect of antibodies binding to toxins?

A

Neutralizes the toxins by preventing them from affecting human cells

129
Q

How do antibodies prevent pathogens from binding to human cells?

A

By blocking the cell surface receptors that pathogens need to attach to host cells

130
Q

What are the two forms of antibodies?

A

Membrane-bound and secreted

Membrane-bound antibodies have an extra section of protein that anchors them to the B cell membrane.

131
Q

What is the process called that copies a gene into mRNA?

A

Transcription

132
Q

What are introns?

A

Sections of DNA that do not code for amino acids

133
Q

What are exons?

A

Sections of DNA that do code for amino acids

134
Q

What is pre-mRNA?

A

mRNA strands containing both introns and exons

135
Q

What is splicing?

A

The process of removing introns and joining exons to form mRNA strands

136
Q

What is alternative splicing?

A

The process where certain exons are removed along with introns to form different mRNA strands

137
Q

What percentage of human genes undergo alternative splicing?

A

About 95%

138
Q

How can one gene give rise to more than one protein?

A

By modifying the mRNA before it’s translated into protein through alternative splicing

139
Q

What cells do activated B cells divide into?

A

Plasma cells and memory B cells

140
Q

True or False: Antibodies can only be found in a secreted form.

A

False

141
Q

What is the role of macrophages in T cell activation?

A

Engulf pathogens and present antigens to T cells

142
Q

What structures are found on the surface of T cells that bind to antigens?

A

T cell receptors

143
Q

What activates the immune system when a pathogen enters the body for the first time?

A

The antigens on the pathogen’s surface activate the immune system.

144
Q

What are the two components of the primary immune response?

A
  • Non-specific immune response
  • Specific immune response
145
Q

Why is the primary response slow?

A

There aren’t many B cells that can make the antibody needed to bind to the antigen.

146
Q

What happens after the body produces enough of the right antibody during the primary response?

A

The infected person will show symptoms of the disease.

147
Q

What are memory cells and what role do they play in immunity?

A

Memory cells remain in the body for a long time and help the immune system respond quicker during a second exposure.

148
Q

What do B memory cells record?

A

The specific antibodies needed to bind to the antigen.

149
Q

What is the secondary immune response?

A

The immune response that occurs when the same pathogen enters the body again, producing a quicker and stronger response.

150
Q

What do memory cells divide into during the secondary response?

A
  • Plasma cells (B effector cells)
  • Cells that produce the right antibody to the antigen
151
Q

What are the two types of active immunity?

A
  • Natural - immunity after catching a disease
  • Artificial - immunity after vaccination
152
Q

What is passive immunity?

A

Immunity obtained from being given antibodies made by a different organism.

153
Q

What are the two types of passive immunity?

A
  • Natural - antibodies received from the mother
  • Artificial - injected with antibodies
154
Q

How do vaccines provide immunity?

A

Vaccines contain antigens that stimulate the primary immune response without causing the disease.

155
Q

What is one method by which some vaccines work?

A

Some vaccines use mRNA to instruct cells to produce antigens.

156
Q

What is antigenic variation?

A

The process that creates different strains of pathogens due to mutations in antigen proteins.

157
Q

What is one evasion mechanism of HIV?

A

HIV kills immune system cells it infects, reducing the number of cells available to detect HIV.

158
Q

How does HIV’s high mutation rate affect the immune response?

A

It results in new strains of the virus, requiring a primary response each time a new strain appears.

159
Q

How does Mycobacterium tuberculosis evade the immune system?

A

It produces substances that prevent the lysosome from fusing with the phagocytic vacuole, allowing it to multiply undetected.

160
Q

Fill in the blank: The production of memory cells gives _______.

A

[immunity]

161
Q

True or False: Active immunity is acquired only through vaccinations.

A

False

162
Q

Describe the role of B memory cells in the secondary response.

A

B memory cells rapidly produce the specific antibodies needed when re-exposed to the same antigen.

163
Q

State two differences between active and passive immunity.

A
  • Active immunity involves the individual’s immune system producing antibodies
  • Passive immunity involves receiving antibodies from another organism
164
Q

Describe how a vaccine gives immunity to a pathogen.

A

A vaccine contains antigens that stimulate the primary immune response without causing disease.

165
Q

Describe one way in which Mycobacterium tuberculosis evades the immune system.

A

It prevents lysosome fusion with phagocytic vacuoles, allowing it to multiply undetected.

166
Q

What are antibiotics?

A

Chemicals that kill or inhibit the growth of microorganisms

Antibiotics are used to treat bacterial infections.

167
Q

What are bacteriocidal antibiotics?

A

Antibiotics that kill bacteria

Examples include penicillin and amoxicillin.

168
Q

What are bacteriostatic antibiotics?

A

Antibiotics that prevent bacteria from growing

They inhibit bacterial metabolism without killing the bacteria.

169
Q

How do antibiotics work?

A

By inhibiting bacterial metabolism

They interfere with growth and life processes of the cell.

170
Q

What is one way antibiotics inhibit bacterial growth?

A

By inhibiting enzymes needed to make chemical bonds in bacterial cell walls

This results in weakened cell walls that can lead to cell death.

171
Q

How do antibiotics affect protein production in bacteria?

A

They bind to bacterial ribosomes, inhibiting protein synthesis

Without protein production, bacteria can’t carry out essential metabolic processes.

172
Q

What is a clear zone (inhibition zone)?

A

A clear patch in the lawn of bacteria where growth is inhibited by an antibiotic

The size of the clear zone indicates the effectiveness of the antibiotic.

173
Q

What is the importance of aseptic techniques in antibiotic investigations?

A

To prevent contamination of bacterial cultures with unwanted microorganisms

Contamination can affect results and pose health risks.

174
Q

What are some aseptic techniques?

A

Regular disinfection of surfaces, using sterile equipment, working near a Bunsen burner

These techniques minimize contamination in bacterial cultures.

175
Q

What are hospital-acquired infections (HAIs)?

A

Infections that patients acquire during their hospital stay

They can be caused by antibiotic-resistant bacteria.

176
Q

What can contribute to the development of antibiotic resistance in bacteria?

A

Overprescribing antibiotics and improper use by patients

This can lead to serious health problems and difficulty in treating infections.

177
Q

List some codes of practice to prevent antibiotic resistance.

A
  • Avoid prescribing antibiotics for minor infections
  • Use narrow-spectrum antibiotics
  • Rotate the use of different antibiotics
  • Ensure patients complete their prescribed course

These practices help reduce the likelihood of bacterial resistance.

178
Q

True or False: Antibiotics are effective against viral infections.

A

False

Antibiotics are designed to target bacteria, not viruses.

179
Q

Fill in the blank: The size of a clear zone indicates how well an antibiotic __________.

A

works against bacteria

A larger clear zone means greater inhibition of bacterial growth.

180
Q

Name two processes in a bacterial cell that antibiotics can inhibit.

A
  • Enzyme activity in cell wall synthesis
  • Protein synthesis

These processes are essential for bacterial growth and survival.

181
Q

What should doctors avoid when prescribing antibiotics?

A

Prescribing them for viral infections and for preventive measures

This helps to minimize the development of antibiotic resistance.

182
Q

What happens to bacteria when they are exposed to antibiotics?

A

They may evolve resistance and survive despite treatment

This can lead to more severe infections and complications.

Biology Edexcel Sophie (8 decks)

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